PMM-7 Add metrics test for QAN

[maxkondr]

Ticket number: PMM-7

Percona-Lab/pmm-submodules#4387

[maxkondr]

@copilot review

[Copilot]

Pull request overview

This PR adds ClickHouse-backed integration tests for QAN metrics and aligns the database helper code under the models package, along with Makefile improvements for standing up a local ClickHouse test environment.

Changes:

• Added integration tests for Metrics methods (Get, SelectQueryExamples, SchemaByQueryID, ExplainFingerprintByQueryID) against ClickHouse fixtures.
• Moved QAN DB helpers from package main to package models and updated main.go call sites accordingly.
• Improved qan-api2/Makefile test environment targets (container startup + readiness wait + clearer help).

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
qan-api2/models/metrics_test.go	New ClickHouse integration tests for QAN metrics APIs.
qan-api2/models/db.go	Switched package to models (exported DB helpers used by main.go).
qan-api2/models/db_test.go	Refactored ClickHouse partition/db-creation tests (docker exec + migrations/fixtures).
qan-api2/Makefile	Updated help/default goal and improved test container startup flow.
qan-api2/main.go	Updated references to DB helpers now living in models.

Comments suppressed due to low confidence (3)

qan-api2/models/db.go:17

• The package-level doc comment still says Package main., but the file now declares package models. That makes generated docs misleading and breaks the Go convention that the doc comment must match the package name and sit immediately above the package clause (no blank line in between).
  qan-api2/models/db_test.go:125
• TestCreateDbIfNotExists creates pmm_created_db but never cleans it up, and it also runs in parallel despite using the shared ClickHouse Docker container. This can leave state behind and/or race with other tests that drop/create databases in the same container.
  qan-api2/models/db_test.go:83
• t.Parallel() here can race with other ClickHouse-integration tests because this test uses a shared Docker container and fixed database names (pmm_test_parts, pmm_created_db). In particular, the cleanup drops pmm_created_db, which can collide with TestCreateDbIfNotExists if they run in parallel. Run this test serially or use per-test unique database names.

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[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 42.54%. Comparing base (e72363c) to head (4e36fea).
⚠️ Report is 1 commits behind head on v3.

Additional details and impacted files

@@            Coverage Diff             @@
##               v3    #5446      +/-   ##
==========================================
- Coverage   43.17%   42.54%   -0.64%     
==========================================
  Files         413      413              
  Lines       42325    42325              
==========================================
- Hits        18275    18006     -269     
- Misses      22179    22476     +297     
+ Partials     1871     1843      -28     

Flag	Coverage Δ
admin	34.69% <ø> (ø)
agent	46.53% <ø> (-2.61%)	⬇️
managed	42.32% <ø> (-0.01%)	⬇️
vmproxy	72.41% <ø> (ø)

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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.

[it-percona-cla]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you all sign our Contributor License Agreement before we can accept your contribution.
1 out of 2 committers have signed the CLA.

✅ maxkondr
❌ Copilot
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[Copilot]

Pull request overview

Copilot reviewed 5 out of 5 changed files in this pull request and generated 6 comments.